The facial nerve, also known as the seventh cranial nerve, is a nerve that originates in the brain stem and supplies the muscles of the face. It contains both motor and sensory fibers and is responsible for the movement of facial muscles, the sense of taste in the front two-thirds of the tongue, and the secretion of the tear and saliva glands. This article will discuss the branches of the facial nerve.
Supraorbital and Supratrochlear Branches
The supraorbital and supratrochlear branches of the facial nerve are the first branches to emerge from the main facial nerve trunk. The supraorbital branch exits the facial nerve at the upper edge of the orbit and innervates the forehead muscles. The supratrochlear branch exits the facial nerve at the upper edge of the orbit and innervates the medial part of the orbit.
Zygomatic and Buccal Branches
The zygomatic and buccal branches of the facial nerve emerge from the main facial nerve trunk just below the supraorbital and supratrochlear branches and travel in different directions. The zygomatic branch exits the facial nerve and innervates the cheek muscles. The buccal branch exits the facial nerve and innervates the muscles of the cheek, jaw, and chin.
Marginal Mandibular and Cervical Branches
The marginal mandibular and cervical branches of the facial nerve emerge from the main facial nerve trunk below the zygomatic and buccal branches. The marginal mandibular branch exits the facial nerve and innervates the muscles of the lower lip and chin. The cervical branch exits the facial nerve and innervates the muscles of the neck and upper chest.
Temporal and Stylomastoid Branches
The temporal and stylomastoid branches of the facial nerve emerge from the main facial nerve trunk below the marginal mandibular and cervical branches. The temporal branch exits the facial nerve and innervates the muscles of the temple. The stylomastoid branch exits the facial nerve and innervates the muscles of the ear and mastoid process.
